Method and apparatus for applying a material to an object



M y 1964 J. R. SPRAUL ETAL METHOD AND APPARATUS FOR APPLYING A MATERIAL TO AN OBJECT 3 Sheets-Sheet 1 Filed Nov. 3, 1961 I]; B05527 See/r04 Wm omen m LAW 0 N 7 E e M flrromvsys.

May 12, 1964 METHOD AND APPARATUS FOR APPLYING A MATERIAL TO AN OBJECT Filed NOV. 3, 1961 J. R. SPRAUL ETAL 3 Sheets-Sheet 2 .Q r B05527 SPEAK/L msesrr A?- Geese INVENTORS.

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May 12, 1964 J. R. SPRAUL ETAL METHOD AND APPARATUS FOR APPLYING A MATERIAL TO AN OBJEQT s Sheets-Sheet 5 Filed Nov. 3, 1961 r]; Boss/er $PEHUL LELAWD L. PEA/e7- EVERETT A. Geese INVENTORS.

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United States Patent M 3,132,967 METHGI) AND APPARATUS FGR APPLYING A MATERIAL TO AN @EJEQT Joseph Robert Spraul, Palos Verdes Estates, Leland L.

Pear-t, Newport Beach, and Everett A. Greer, Bell Gardens, (Jaliil, assignors to Rheern Manufacturing Company, New York, N.Y., a corporation of California Filed Nov. 3, 1961, Ser. No. 150,040 6 Claims. (Cl. 11852) This invention relates to apparatus for applying a material to an object. It relates more particularly to apparatus for applying a particulate material, such as a powdered resin or a metallic powder, so as to form a coating on a surface of an object. A suggested use is the application of a plastic resin or metallic coating to the internal surface of the head and bottom of a metal shipping container.

As was stated in our application filed October 2, 1961, Serial No. 142,127, pertaining to a Method and Apparatus for Applying a Material to a Body, and pertaining more particularly to coating the interior surface of the body of a metal shipping container, metal shipping containers, such as black steel drums and pails, are used extensively for transporting and storing a wide variety of products, but their effective use can be greatly extended if the inside of such containers is coated with a material resistant to corrosive activities and reactions of products which cannot now be carried and stored in such drums because of such product activities and reactions. By way of example, presently it is not possible or practical to pack products with high acid activity qualities in black steel drums, and often excessively expensive drums, such as stainless steel drums, are used for such purpose.

The application of the method and apparatus described and claimed in said co-pending application, to the bodies of black steel drums, and the application of the apparatus of the present invention to the heads and bottoms of such black steel drums will produce fully coated black steel drums at a cost far below the cost of stainless steel drums, and such coated drums will have corrosive-resistant characteristics commercially comparable, and often superior to those of substantially more expensive stainless steel drums.

Various corrosive-resistant coatings have been applied by many methods, such as painting or dipping, to heads and bottoms of drums in order to build up their corrosiveresistant capacities, but many limitations have been encountered. For instance, several of the coating materials are relatively expensive. But more important are the considerations that such coatings are often inefficient in that they leave voids created by air bubbles or give an incomplete coverage to the surfaces to which they are applied; the coatings formed thereby are excessively thin; they often become brittle and break away from the heads or bottoms; and it is generally impossible or impractical to build up sufficiently dense coatings by repeated applications of layers of coatings.

The apparatus of the present invention, on the other hand, make it commercially feasible to apply quickly, easily, and relatively inexpensively, a single, firm, solid, complete coating of corrosive-resistant material to the entire surface of the head or bottom of a standard black steel shipping container, or to selected surface areas, free of voids, in a single coating operation, so that the black steel head or bottom so treated has all of the corrosiveresistant characteristics of more expensive metals, such as stainless steel.

It is therefore an object of the present invention to provide apparatus for applying a resinous or metallic powder to the surface of a metallic object so as to form a solid coating thereon.

It is another object of the invention to provide ap- 3,132,967 Patented May 12, 1964:

ICE

paratus for applying such a coating to the head and bottom members of metal shipping container, before or after the assembly of the container, so as to render said container resistant to corrosive activities and reactions of products packed therein.

It is still another object of the invention to provide apparatus for applying such a coating of substantial thickness in a single application.

It is a further object of the invention to provide apparatus for applying such a coating, which are relatively simple and readily adaptable for use in association with modern, high-speed steel container production lines.

With these and other objects in view, the invention consists of the construction, arrangement and combination of the various parts of the device whereby the objects contemplated are attained, as hereinafter set forth, pointed out in the appended claims, and illustrated in the accompanying drawings.

In the drawings:

FIGURE 1 is a side elevational view of the apparatus of the present invention.

FIGURE 2 is a front elevational view of said apparatus.

FIGURE 3 is an enlarged cross-sectional view taken on line 3-3 of FIGURE 1.

FIGURE 4 is a cut-away view similar to FIGURE 3, but showing the piston in extended position.

FIGURE 5 is a further enlarged view showing a detail of the apparatus illustrated in FIGURE 4.

FIGURE 6 is a View similar to FIGURE 3, but with the apparatus in dumping position.

FIGURE 7 is a front elevational view form of the apparatus.

FIGURE 8 is an enlarged view showing a detail of the apparatus illustrated in FIGURE 7, but in dumping position.

FIGURE 9 is a view taken on line 9-9 of FIGURES.

FIGURE 10 is an enlarged view taken on line 101i) of FIGURE 7.

A supporting frame 10 serves as an open top bench and has legs 11 and transverse brace members 12 and 13. Vertical arms 14 and 15 extend upwardly from supporting frame 10, and in turn support horizontal arms 16 and 17, which are in the same plane as each other, but are spaced apart from each other so as to leave a substantial open space 18 therebetween.

Vertically mounted on arms 16 and 17, in substantially parallel relationship to each other to define said open space 18, are arms 20. Disposed between and supported by said arms 20 is a hopper 21.

The bottom 22 of hopper 21 is preferably funnel-shaped and has an open end 23 in which a downwardly directed, hollow tubular member 24 is disposed. Mounted on tubular member 24 is a collar 25. A lever arm 26 is mounted on a rotatable shaft 27, which passes through collar 25 and tubular member 24 to the inside of tubular member 24, where it is connected to suitable sifter means, or a valve, such as a butterfly valve (not shown), disposed so as to selectively retain or release powder stored in hopper 21. A deflecting cone 28 and a vane 29 are mounted on the lower open end of tubular member 24. Preferably, cone 28 and vane 29 are disposed with their lower open ends below the plane of arms 16 and 17.

\A support frame 30 may be mounted on hopper 21 to support a sock or conduit 31, which has access to the interior of hopper 21, said access being provided by any suitable means, such as a collar 32. Sock 31 may be utilized to release air pressure in hopper 21.

Supporting frame 10 has internally disposed therein a bin 40, the bottom 41 of which is funnel-shaped and has an open lower end 42 in which a downwardly directed hollow tube 43 is disposed. A T-connector 44 is mounted on the lower end of tube 43. An air pressure line 45 is of a modified connected to one side of T-connector 44, and a hollow tube or conduit 46 is connected at one end 47 thereof to the other side of T-co-nnector 44. The other end 48 of conduit 46 is connected to hopper 21.

A frame is rotatably suspended in bin 4d. Suspension is attained by supporting the upper end 51 on shafts 52 and 53, which are rotatably supported as at 54- and 55 respectively, on supporting frame 10. Shaft 53 extends externally from supporting frame 16, and a crank arm 56 is mounted on the protruding end 57 of shaft 53.

Mounted in frame 55 is a fluid system cylinder and piston assembly 69, which has a cylinder 61 disposed in upright position in frame 50 at substantially the center of frame Stl. A piston rod d2 projects upwardly from cylinder 61. Mounted on the upper end of piston rod 62 is a support and centering platform member 63. A valve 64 may be mounted on supporting frame and operatively connected to cylinder and piston assembly 60 by connection means (not shown) so as to selectively move piston rod 62 and platform 63 up and down in a vertical plane.

A tray member 70, preferably cylindrical, has a side wall '71, and a bottom 72 which has a centrally located opening '73 designed to receive a drum head or bottom or other object to be coated. Seated on said bottom 72 and secured thereto by any suitable means, such as bolts '74, is a fiat ring '75, which preferably has a beveled internal edge '76. Ring is is disposed in tray '71 so that its central opening overlies opening 7 3 of tray '79. Ring '75 may have an annular groove 77 formed in the bottom surface thereof.

Bottom 72 of tray 73 is mounted on upper end frame 50.

In the drawings, the object to be coated is designated by the numeral 2%.

In the modified form of the apparatus illustrated in FIGURES 710 of the drawings, an alternative form of hopper suspension may be provided. As best shown in FIGURE 7, in said modified form, a single vertical arm 1% and a single horizontal arm 1131 are provided. Mounted on arm 1131 is a ring 102 which receives a hopper 103, preferably of cylindrical configuration.

The bottom N4 of hopper 163 has mounted thereon a sifter feed assembly 110, which may comprise overlying discs 111 and 112, slidably mounted on each other, said 1 discs 111 and 112 having spaced apart openings therein, the openings in one disc being disposed so as to be selectively aligned with either the openings or the solid surface portions of the other disc, for selectively opening or closing the bottom 164 of hopper 16 3. Disc 111 may be supported on rollers 113 mounted on hopper 103 as by brackets 114, and other rollers 115 may be mounted on hopper 114 so as to abut against the edge of disc 111, said rollers 113 and 11.5 serving to aid the selective sliding movement of disc 111 on disc 112.

A fluid system cylinder and piston assembly 120 may be pivotally mounted at one end thereof on hopper 183 by any suitable means, such as a bracket 121. The free end 122 of a piston rod 123 is pivotally connected to one end of a rocker arm 124. The other end of said rocker arm is mounted on disc 111. Disc 111 may thus he slidably moved on disc 112 to open or closed positions by actuation of fiuid system assembly 120.

In said modified form of apparatus, frame 50 and fluid system assembly 61) may be eliminated, in which case a clamping system is provided to maintain the object to be coated in opening '73 of tray 76. For that purpose, tray iii is mounted on and supported by a transverse plate 133. Flate 130 has mounted thereon protruding shafts 131 and 132. Shafts 131 and 132 are rotatably mounted on supporting frame 119. Pivotally mounted on the under side of plate 13%, adjacent opening 73, and spaced apart from each other, are a plurality of roekerarms 140, the free ends of which extend into the plane of opening '73.

Rocker arms 146 may be pivotally mounted on plate by means of mounting plates 141, and each of said mounting plates 1-11 may also support a fluid system cylinder and piston assembly 142 pivotally mounted thereon. The free end 143 of each piston rod 144 of each of said fluid system assemblies 142 is pivotally connected to a rocker arm 149.

Shaft 131 has a free end 133 which protrudes beyond supporting frame 16. Mounted on end 133 of shaft 131 is a sprocket 134, on which an endless chain drive is mounted. Chain drive 135 is also mounted on a sprocket 136 which is driven by a power source, such as a motor 1.37.

Referring first to the form of the apparatus illustrated in FIGURES 16 of the drawings, a quantity of resinous or metallic powder is introduced into hopper 21 by way of conduit 46.

When a drum head is the object to be coated, it is heated in an oven (not shown) until it reaches :a temperature suificient to cause the powder later deposited thereon to flow, and to substantially maintain that temperature during the coating operation. In practice it has been found that when a black steel drum head is to be coated witha polyethylene powder, heating to a temperature of approximately 457 F. gives satisfactory results, but it will be understood that the temperature will vary with different metals, various gauges of metals, and kind of powder to be applied thereto.

After heating, drum. head 200'is removed from .the oven and placed in the iappanatus of the present invention, with the surface of the drum head which is to be the interior surface when the drum head is mounted on a drum body, facing upward. Drum head 2% is placed on support and centering platform member '63, which is disposed substantially at the center of the drum head 200. Drum head 200 is then in position directly under opening 73 in tray A ring 75 of proper dimension to fit head 200 has meanwhile been seated on and secured to bottom 72 of may '70.

Fluid system cylinder and piston assembly 60 is then actuated to dispose drum head 200 in opening 73.

It will be recognized that, as illustnated in the drawings,

drum heads generally have a curl area adjacent their peripheral edge, the curl area being designed .to fit over a mating curled lip on a drum body to which the drum head is to be applied. On some containers, such as socalled tighthead drums, it may not be desirable to apply :a coating to the inside surface of said curl area of a head, principally because a double seam of the drum head on the drum body is used, and it is desirable to eliminate excess material in the double seam area Under such conditions, a. ring 75 is'provided with a beveled edge 76, the pointed edge of which will be disposed so as to mask the portion of the surface of the curl area where no coating is wanted, as best illustrated in FIGURE 5 of the drawings. Ring 75 is also provided with an annular groove 77 disposed so as to receive the outer peripheral edge of drum head 200, which in drum manufacture is generally upturned, again as best illustrated inFIGUR'E 5. When drum head 200 is thus disposed in opening 73 in abutment with ring 75, it is held in that position by cylinder and piston assembly 60.

By manipulation of lever arm 26, a quantity of powder is then discharged from hopper 241 and falls into tray 70. Sufficient powder is discharged from hopper 21 to cover the entire exposed surface of heated drum head 200. The powder is then disposed in tray 70, as illustrated in FIG- URE 5.

On contact with the surface of heated drum head 290, the particles of powder deposited thereon will soften, flow and coalesce into one continuous mass to form a strongly bonded coating on the exposed drum head surface. In practice, it has been found that a very satisfactory 15 mil coating is attained after approxirnately four to live seconds, but again it will be recognized that this is merely an example and is not intended as a Limitation, and that the thickness :of the coating and the time of con tact of the powder with the object will vary, for instance, according to the kind of powder used and the heat of the object being coated.

After the proper elapsed time, crank 56 is manipulated to rotate frame 50 and tray 70, whereupon the apparatus will assume the position illustrated in FIGURE 6, and all excess powder which has not adhered to heated head 2% will drop into bin 41 Crank 56 is again manipulated to return frame 50 and tray 70 to their originnal positions. Cylinder and piston assembly 60 is then activated to lower platform 63, with drum 'head are seated thereon, and drum head are is then removed from the apparatus.

Frequently, it has been found advantageous, but not essential, to post-heat drum head 20% after it has received its coating. The operation hereinabove described produces a substantially uniform coating of substantial thickness, clear of voids, over the entire exposed surface of drum head 200, but at times post heating will produce a more uniform coating. For post-heating, drum head 2% is returned to the oven after coating. It has been found that post-heating for nine minutes at 400 F. gives satisfactory results, but again this time and temperature are given as examples, and not as limitations, the time and temperature being varied, dependent on the material being coated and the powder used, and post-heating time and temperature, in any event, are not critical.

It be readily seen that if, instead of masking the flange of head 200, it is desired to apply a coating to the inside surface of the flange, a ring 75 may be provided which, instead of overlying said flange, will be designed to meet the peripheral edge of drum 200, or the outside edge of any other object to be coated, exposing the entire surface to the powder, and producing a coating over said entire exposed surface.

When a quantity of excess powder has collected in bin 40, and it is desired to return such excess powder to hop per 21 for reuse, air pressure is introduced into air pressure line 45, and excess powder dropping through T-connector 44 will be blown through tube 46 and returned to hopper 21.

Now referring to the modified form of the apparatus illustrated in FIGURES 7-10 of the drawings, a quantity of powder is similarly introduced into hopper 103.

Heated drum head 200 is then brought into position under opening 73 in tray 70, and cylinder and piston assemblies 142 are activated, and rocker arms 14% are thus moved to bring the free ends thereof into contact with the under surface of drum head 200 to move drum head 200 into opening 73 and to clamp it into abutting position against ring 75 and retain it in that position.

Cylinder and piston assembly 120 is then activated to align the openings in disc 111 with the openings in disc 112 and allow the powder in hopper 103 to flow and be deposited in tray 70.

After coating has been accomplished in the manner hereinabove described, and after the time interval mentioned, power source 137 is activated, and chain drive 135 will cause shaft 131 and tray 70 to rotate, whereupon the apparatus assume the position illustrated in FIG- URE 8. All excess powder which has not adhered to drum head 200 will drop into bin 40. Power source 137 is then again activated to return tray 70 to its original position.

Cylinder and piston assemblies 142 are then again activated to move rocker arms 140, thus permitting drum head 200 to move out of contact with ring 75, out of opening 73, and in position to be removed from the apparatus.

Excess powder in bin 40 may be returned to hopper 103 in a manner similar to that hereinabove described.

Although the invention has been herein shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom Within the scope of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent structures and methods.

What is claimed is:

1. Apparatus for applying a particulate material to a heated body so as to form a coating on one surface thereof which comprises: a supporting frame; a hopper supported by said frame and adapted to receive and discharge said particulate material; means adjacent the bottom of said hopper for selectively retaining and discharging said particulate material, and spreading particulate material discharged from said hopper; a tray rotatably mounted on said frame in suspended position below said hopper so as to receive and retain particulate material discharged from said hopper; said tray having an opening in the bottom thereof to receive said heated body; a flat ring internally mounted on the bottom of said tray and extending into said opening; means for disposing and retaining said heated body in said opening in abutment with said ring; and means for rotating said tray so as to discharge particulate material therefrom.

2. Apparatus as defined in claim 1, wherein said ring is disposed so as to mask portions of said heated body against contact with said particulate material.

3. Apparatus for applying a particulate material to a heated body so as to form a coating on one surface thereof which comprises: a hopper mounted in elevated position and adapted to receive, retain and discharge said particulate material; means adjacent the bottom of said hopper for selectively retaining and rapidly discharging and spreading said particulate material over a broad area; a supporting frame; a rotatable tray mounted on said frame below said hopper, in position to receive particulate material discharged from said hopper, said tray having a centrally disposed opening to receive said heated body; a frame suspended from said tray; a fluid system cylinder supported by said suspended frame; a piston rod protruding upwardly from said cylinder; a platform mounted on the free end of said piston rod and adapted to support and center said heated body in said opening; and means for rotating said tray so as to discharge particulate material from said tray.

4. Apparatus for applying a particulate material to a heated body so as to form a coating on one surface thereof which comprises: a hopper mounted in elevated position and adapted to receive, retain and discharge said particulate material; means adjacent the bottom of said hopper for selectively retaining and rapidly discharging and spreading said particulate material over a broad area; a supporting frame; a rotatable tray mounted on said frame below said hopper, in position to receive particulate material discharged from said hopper, said tray having a centrally disposed opening to receive said heated body; a transverse plate supporting said tray; rocker arms suspended =from said plate adjacent the opening in said tray and adapted to support said heated body in said open ing; and means for rotating said tray so as to discharge particulate material from said tray.

5. Apparatus as defined in claim 4, including power actuating means for moving said rocker arms so as to move said heated body into and out of said opening.

6. Apparatus as defined in claim 5, wherein said power actuating means comprises fluid system cylinder and piston assemblies.

References Cited in the file of this patent UNITED STATES PATENTS 907,3 65'- Huebner Dec. 22, 1908 1,721,866 Junge July 23, 1929 2,119,093 Voris Sept. 27, 1955 2,737,461 Heisler Mar. 6, 1956 2,844,489 Gemmer July 22, 1958 

1. APPARATUS FOR APPLYING A PARTICULATE MATERIAL TO A HEATED BODY SO AS TO FORM A COATING ON ONE SURFACE THEREOF WHICH COMPRISES: A SUPPORTING FRAME; A HOPPER SUPPORTED BY SAID FRAME AND ADPATED TO RECEIVE AND DISCHARGE SAID PARTICULATE MATERIAL; MEAND ADJACENT THE BOTTOM OF SAID HOPPER FOR SELECTIVELY RETAINING AND DISCHARGING SAID PARTICULATE MATERIAL, AND SPREADING PARTICULATE MATERIAL DISCHAGE FROM SAID HOPPER; A TRAY ROTATABLY MOUNTED ON SAID FRAME IN SUSPENDED POSITION BELOW SAID HOPPER SO AS TO RECEIVE AND RETAIN PARTICULATE MATERIAL DISCHARGED FROM SAID HOPPER; SIAD TRAY HAVING AN OPENING IN THE BOTTOM THEREOF TO RECEIVE SAID HEATED BODY; A FLAT RING INTERNALLY MOUNTED ON THE BOTTOM OF SAID TRAY AND EXTENDING INTO SAID OPENING; MEANS FOR DISPOSING AND RETAINING SAID HEATED BODY IN SAID OPENING IN ABUTMENT WITH SAID RING; AND MEANS FOR ROTATING SAID TRAY SO AS TO DISCHARGE PARTICULATE MATERIAL THEREFROM. 